Commit Graph

57 Commits

Author SHA1 Message Date
Peter Wemm
6875d25465 Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.
1997-02-22 09:48:43 +00:00
Jordan K. Hubbard
1130b656e5 Make the long-awaited change from $Id$ to $FreeBSD$
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore.  This update would have been
insane otherwise.
1997-01-14 07:20:47 +00:00
Bill Fenner
39172c9401 Re-enable the TCP SYN-attack protection code. I was the one who didn't
understand the socket state flag.

2.2 candidate.
1996-11-10 07:37:24 +00:00
Paul Traina
a51764a8bf Fix two bugs I accidently put into the syn code at the last minute
(yes I had tested the hell out of this).

I've also temporarily disabled the code so that it behaves as it previously
did (tail drop's the syns) pending discussion with fenner about some socket
state flags that I don't fully understand.

Submitted by:	fenner
1996-10-11 19:26:42 +00:00
David Greenman
6d6a026b47 Improved in_pcblookuphash() to support wildcarding, and changed relavent
callers of it to take advantage of this. This reduces new connection
request overhead in the face of a large number of PCBs in the system.
Thanks to David Filo <filo@yahoo.com> for suggesting this and providing
a sample implementation (which wasn't used, but showed that it could be
done).

Reviewed by:	wollman
1996-10-07 19:06:12 +00:00
Paul Traina
ebb0cbea75 Increase robustness of FreeBSD against high-rate connection attempt
denial of service attacks.

Reviewed by:	bde,wollman,olah
Inspired by:	vjs@sgi.com
1996-10-07 04:32:42 +00:00
Paul Traina
12eafeb016 I don't understand, I committed this fix (move a counter and fixed a typo)
this evening.

I think I'm going insane.
1996-09-21 06:39:20 +00:00
Andrey A. Chernov
96d719e6e0 Syntax error: so_incom -> so_incomp 1996-09-21 06:30:06 +00:00
Paul Traina
4195b4af58 If the incomplete listen queue for a given socket is full,
drop the oldest entry in the queue.

There was a fair bit of discussion as to whether or not the
proper action is to drop a random entry in the queue.  It's
my conclusion that a random drop is better than a head drop,
however profiling this section of code (done by John Capo)
shows that a head-drop results in a significant performance
increase.

There are scenarios where a random drop is more appropriate.
If I find one in reality, I'll add the random drop code under
a conditional.

Obtained from: discussions and code done by Vernon Schryver (vjs@sgi.com).
1996-09-20 21:25:18 +00:00
Paul Traina
7b40aa327d Make the misnamed tcp initial keepalive timer value (which is really the
time, in seconds, that state for non-established TCP sessions stays about)
a sysctl modifyable variable.

[part 1 of two commits, I just realized I can't play with the indices as
 I was typing this commit message.]
1996-09-13 23:51:44 +00:00
Paul Traina
7ff19458de Receipt of two SYN's are sufficient to set the t_timer[TCPT_KEEP]
to "keepidle".  this should not occur unless the connection has
been established via the 3-way handshake which requires an ACK

Submitted by:	jmb
Obtained from:	problem discussed in Stevens vol. 3
1996-09-13 18:47:03 +00:00
Bill Fenner
df5c0b8a7a Back out my stupid braino; I was thinking strlen and not sizeof. 1996-05-02 05:54:14 +00:00
Bill Fenner
af00f8007c Size temp var correctly; buf[4*sizeof "123"] is not long enough
to store "192.252.119.189\0".
1996-05-02 05:31:13 +00:00
Andrey A. Chernov
75cfc95fe2 inet_ntoa buffer was evaluated twice in log_in_vain, fix it.
Thanx to: jdp
1996-04-27 18:19:12 +00:00
Garrett Wollman
a2352fc148 Delete #ifdef notdef blocks containing old method of srtt calculation.
Requested by: davidg
1996-04-26 18:32:58 +00:00
Paul Traina
d78a37ad5a Logging UDP and TCP connection attempts should not be enabled by default.
It's trivial to create a denial of service attack on a box so enabled.

These messages, if enabled at all, must be rate-limited. (!)
1996-04-09 07:01:53 +00:00
Poul-Henning Kamp
816a3d836e Log TCP syn packets for ports we don't listen on.
Controlled by: sysctl net.inet.tcp.log_in_vain: 1

Log UDP syn packets for ports we don't listen on.
Controlled by: sysctl net.inet.udp.log_in_vain: 1

Suggested by:	Warren Toomey <wkt@cs.adfa.oz.au>
1996-04-04 10:46:44 +00:00
Garrett Wollman
9e2874b067 Slight modification of RTO floor calculation. 1996-03-25 20:13:21 +00:00
Garrett Wollman
233e8c18e8 A number of performance-reducing flaws fixed based on comments
from Larry Peterson &co. at Arizona:

- Header prediction for ACKs did not exclude Fast Retransmit/Recovery.
- srtt calculation tended to get ``stuck'' and could never decrease
  when below 8.  It still can't, but the scaling factors are adjusted
  so that this artifact does not cause as bad an effect on the RTO
  value as it used to.

The paper also points out the incr/8 error that has been long since fixed,
and the problems with ACKing frequency resulting from the use of options
which I suspect to be fixed already as well (as part of the T/TCP work).

Obtained from:	Brakmo & Peterson, ``Performance Problems in BSD4.4 TCP''
1996-03-22 18:09:21 +00:00
David Greenman
2ee45d7d28 Move or add #include <queue.h> in preparation for upcoming struct socket
changes.
1996-03-11 15:13:58 +00:00
Guido van Rooij
1347f5b8e5 Add a counter for the number of times the listen queue was overflowed to
the tcpstat structure. (netstat -s)
Reviewed by:	wollman
Obtained from: Steves, TCP/IP Ill. vol.3, page 189
1996-02-26 21:47:13 +00:00
David Greenman
f9d5a964af Fixed bug in Path MTU Discovery that caused the system to have to re-
discover the Path MTU for each connection if the connecting host didn't
offer an initial MSS.

Submitted by:	davidg & olah
1996-02-22 11:46:39 +00:00
Andras Olah
07e43e10f8 Fix a bug related to the interworking of T/TCP and window scaling:
when a connection enters the ESTBLS state using T/TCP, then window
scaling wasn't properly handled.  The fix is twofold.

1) When the 3WHS completes, make sure that we update our window
scaling state variables.

2) When setting the `virtual advertized window', then make sure
that we do not try to offer a window that is larger than the maximum
window without scaling (TCP_MAXWIN).

Reviewed by:	davidg
Reported by:	Jerry Chen <chen@Ipsilon.COM>
1996-01-31 08:22:24 +00:00
Poul-Henning Kamp
f708ef1b9e Another mega commit to staticize things. 1995-12-14 09:55:16 +00:00
Poul-Henning Kamp
0312fbe97d New style sysctl & staticize alot of stuff. 1995-11-14 20:34:56 +00:00
Poul-Henning Kamp
98163b98dc Start adding new style sysctl here too. 1995-11-09 20:23:09 +00:00
Andras Olah
845799c166 Cosmetic changes to processing of segments in the SYN_SENT state:
- remove a redundant condition;
- complete all validity checks on segment before calling
  soisconnected(so).

Reviewed by:	Richard Stevens, davidg, wollman
1995-11-03 22:31:54 +00:00
Garrett Wollman
91badc866f Routes can be asymmetric. Always offer to /accept/ an MSS of up to the
capacity of the link, even if the route's MTU indicates that we cannot
send that much in their direction.  (This might actually make it possible
to test Path MTU discovery in a useful variety of cases.)
1995-10-13 16:00:25 +00:00
Garrett Wollman
e79adb8ed6 Finish 4.4-Lite-2 merge: randomize TCP initial sequence numbers
to make ISS-guessing spoofing attacks harder.
1995-10-03 16:54:17 +00:00
Andras Olah
d3eede9d32 Remove a redundant `if' from tcp_reass().
Correct a typo in a comment (SEND_SYN -> NEEDSYN).

Reviewed by:	David Greenman
1995-07-31 10:24:22 +00:00
Garrett Wollman
dd22498271 tcp_input.c - keep track of how many times a route contained a cached rtt
or ssthresh that we were able to use

tcp_var.h - declare tcpstat entries for above; declare tcp_{send,recv}space

in_rmx.c - fill in the MTU and pipe sizes with the defaults TCP would have
	used anyway in the absence of values here
1995-07-10 15:39:16 +00:00
Garrett Wollman
fc97827135 Keep track of the number of samples through the srtt filter so that we
know better when to cache values in the route, rather than relying on a
heuristic involving sequence numbers that broke when tcp_sendspace
was increased to 16k.
1995-06-29 18:11:24 +00:00
Rodney W. Grimes
9b2e535452 Remove trailing whitespace. 1995-05-30 08:16:23 +00:00
David Greenman
6b067b0744 #ifdef'd my Nagel/ACK hack with "TCP_ACK_HACK", disabled by default. I'm
currently considering reducing the TCP fasttimo to 100ms to help improve
things, but this would be done as a seperate step at some point in the
future.
This was done because it was causing some sometimes serious performance
problems with T/TCP.
1995-05-11 01:41:06 +00:00
Andras Olah
40db8ef747 Fix a misspelled constant in tcp_input.c.
On Tue, 09 May 1995 04:35:27 PDT, Richard Stevens wrote:
> In tcp_dooptions() under the case TCPOPT_CC there is an assignment
>
>       to->to_flag |= TCPOPT_CC;
>
> that should be
>
>       to->to_flag |= TOF_CC;
>
> I haven't thought through the ramifications of what's been happening ...
>
>       Rich Stevens

Submitted by:	rstevens@noao.edu (Richard Stevens)
1995-05-09 12:32:06 +00:00
David Greenman
0d7b7d3ea7 Changed in_pcblookuphash() to not automatically call in_pcblookup() if
the lookup fails. Updated callers to deal with this. Call in_pcblookuphash
instead of in_pcblookup() in in_pcbconnect; this improves performance of
UDP output by about 17% in the standard case.
1995-05-03 07:16:53 +00:00
David Greenman
d79940da0a Further satisfy my paranoia by making sure that the ACKNOW is only
set when ti_len is non-zero.
1995-04-10 17:37:46 +00:00
David Greenman
afa70c96dd Fixed bug I introduced with my Nagel hack which caused tcp_input and
tcp_output to loop endlessly. This was freefall's problem during the past
day.
1995-04-10 17:16:10 +00:00
David Greenman
15bd2b4385 Implemented PCB hashing. Includes new functions in_pcbinshash, in_pcbrehash,
and in_pcblookuphash.
1995-04-09 01:29:31 +00:00
Andras Olah
755c1f07c8 Fix a bug in tcp_input reported by Rick Jones <raj@hpisrdq.cup.hp.com>.
If a goto findpcb occurred during the processing of a segment, the TCP and
IP headers were dropped twice from the mbuf which resulted in data acked
by TCP but not delivered to the user.
Reviewed by:	davidg
1995-04-05 10:32:14 +00:00
David Greenman
e612a582cc Re-apply my "breakage" to the Nagel congestion avoidence. This version
differs slightly in the logic from the previous version; packets are now
acked immediately if the sender set PUSH.
1995-03-27 07:12:24 +00:00
Bruce Evans
b5e8ce9f12 Add and move declarations to fix all of the warnings from `gcc -Wimplicit'
(except in netccitt, netiso and netns) and most of the warnings from
`gcc -Wnested-externs'.  Fix all the bugs found.  There were no serious
ones.
1995-03-16 18:17:34 +00:00
Garrett Wollman
dac2030182 Avoid deadlock situation described by Stevens using his suggested replacement
code.

Obtained from: Stevens, vol. 2, pp. 959-960
1995-02-16 01:39:19 +00:00
Garrett Wollman
41f82abe5a Transaction TCP support now standard. Hack away! 1995-02-16 00:55:44 +00:00
Poul-Henning Kamp
c70f45100d YFfix. 1995-02-14 06:28:25 +00:00
Garrett Wollman
2f96f1f446 Get rid of some unneeded #ifdef TTCP lines. Also, get rid of some
bogus commons declared in header files.
1995-02-14 02:35:19 +00:00
Garrett Wollman
a0292f2375 Merge Transaction TCP, courtesy of Andras Olah <olah@cs.utwente.nl> and
Bob Braden <braden@isi.edu>.

NB: This has not had David's TCP ACK hack re-integrated.  It is not clear
what the correct solution to this problem is, if any.  If a better solution
doesn't pop up in response to this message, I'll put David's code back in
(or he's welcome to do so himself).
1995-02-09 23:13:27 +00:00
Garrett Wollman
10be56487a As suggested by Sally Floyd, don't add the ``small fraction of the window
size'' when doing congestion avoidance.

Submitted by:	Mark Andrews
1994-10-13 18:36:32 +00:00
Poul-Henning Kamp
623ae52e4e GCC cleanup.
Reviewed by:
Submitted by:
Obtained from:
1994-10-02 17:48:58 +00:00
David Greenman
610ee2f9b5 Made TCPDEBUG truely optional. Based on changes I made in FreeBSD 1.1.5.
Fixed somebody's idea of a joke - about the first half of the lines in
in_proto.c were spaced over by one space.
1994-09-15 10:36:56 +00:00